Anti - de Sitter Black Holes in Gauged N = 8 Supergravity

We present new anti-de Sitter black hole solutions of gauged N = 8, SO(8) supergravity, which is the massless sector of the AdS4×S vacuum of M-theory. By focusing on the U(1) Cartan subgroup, we find non-extremal 1, 2, 3 and 4 charge solutions. In the extremal limit, they may preserve up to 1/2, 1/4, 1/8 and 1/8 of the supersymmetry, respectively. In the limit of vanishing SO(8) coupling constant, the solutions reduce to the familiar black holes of the M4×T 7 vacuum, but have very different interpretation since there are no winding states on S and no U -duality. In contrast to the T 7 compactification, moreover, we find no static multi-center solutions. Also in contrast, the S fields appear “already dualized” so that the 4 charges may be all electric or all magnetic rather than 2 electric and 2 magnetic. Curiously, however, the magnetic solutions preserve no supersymmetries. We conjecture that a subset of the extreme electric black holes preserving 1/2 the supersymmetry may be identified with the S Kaluza-Klein spectrum, with the non-abelian SO(8) quantum numbers provided by the fermionic zero modes. 1 Research supported in part by NSF Grant PHY-9722090. 2 Research supported in part by the U. S. Department of Energy under grant no. DOE-91ER40651TASKB.